-- Moore State Machine with Concurrent Output Logic
-- dowload from: www.fpga.com.cn & www.pld.com.cn
library ieee;
use ieee.std_logic_1164.all;
entity moore1 is port(
clk, rst: in std_logic;
id: in std_logic_vector(3 downto 0);
y: out std_logic_vector(1 downto 0));
end moore1;
architecture archmoore1 of moore1 is
type states is (state0, state1, state2, state3, state4);
signal state: states;
begin
moore: process (clk, rst) --this process defines the next state only
begin
if rst='1' then
state <= state0;
elsif (clk'event and clk='1') then
case state is
when state0 =>
if id = x"3" then
state <= state1;
else
state <= state0;
end if;
when state1 =>
state <= state2;
when state2 =>
if id = x"7" then
state <= state3;
else
state <= state2;
end if;
when state3 =>
if id < x"7" then
state <= state0;
elsif id = x"9" then
state <= state4;
else
state <= state3;
end if;
when state4 =>
if id = x"b" then
state <= state0;
else
state <= state4;
end if;
end case;
end if;
end process;
--assign state outputs concurrently;
y <= "00" when (state=state0) else
"10" when (state=state1 or state=state3) else
"11";
end archmoore1;